Looper mechanism for sewing machines



May 4, 1943 s. ZoNls ET AL LOOPER MECHANISM FOR SEWING MACHINES Original Filed March l, 1941 Patented May 4, 1943 slm-.res

LOOPERSMEQHANISMFOR SEWING- MACHINES Sydney Zonis,Y Bridgeport, and ArthurS. Meloy,

Jr., Stratford, Conn., Manufacturing: Comp corporation of New;v J

assignors to The Singer any,v Elizabeth, N; J., a ersey Original application March 1; 1941i SerialiNo;

381,242. Divided all' Claims. This; invention relates:` to looper mechanisms for' sewing machines;- andmore'particularly to= actuating mechanisms`- for rotary; loopersA of the conventional wing-type and complementalto an eye-pOintedneedIe in enchaining'loops of: needlethreadi The object of" tliis` iiiventionv is to provideY a' looperv mechanism adapted tobe easily assembled as aunit` constructionl and embodiedin a sewing machine capable ofhigh speed operation; Other and-more specific" objectsV of the invention will' be f apparent from .the following description and' claims.

This application'isadivision of our prior patent applicationSerialNo. 381,242, filed March 1,

19431, the present invention consisting in the provision of a looper mechanism assembly unit as--hereinafterdescribed inccnnectlon with the accompanying drawing; which illustrates al pre-H ferred' embodiment of the invention and in which:

Fig. ll is a-vertical longitudinal section'of' the" bed-plate and a portion ofthebracket-arm of a sewing machine containing the improved looper' mechanism, the needlev and presser-foot of the machine being shown'Y in front side elevation. Fig. 2 is an'enlarged longitudinal section of the looper: mechanism assembly unit, the'section being-'taken in" a plane containing the axes oirotation of the looperand stub-shafts. Fig. 3 is an enlarged section; transversely of the bedplate, of Athelubricant-containing casing housing the looper-shaft driving gearing.

The'sewng machine in'part illustrated in the drawing has a frame including a work-supporting bed-plate I fromone-end of which rises a hollow standard 2' ofA a conventional bracketarm. The bed-plate I is provided with the usual throat-plate 3 having a needle-aperture 4. Operating through the throat-plate aperture 4 is an eye-pointed thread-carrying needle 5 carried by a vertically endwise reciprocatory needlebar 6.

The work is advanced past the stitch-forming mechanism by a feed-dog 'I of the drop-feed type and which may be actuated in any usual or suitable manner. The feed-dog l, which operates through the suitably slotted throat-plate 3, is opposed in its Work-engaging movement by a presser-foot I8.

Complemental to the needle 5, in the formation of chain stitches, is a conventional Wing-type rotary looper 9. The looper 9 has a shank-pin I0 secured by screws II in one end of a longitudinal bore I2 of a tubular looper-shaft I3. The

d this 'applicatiomApriPHL ing Iiiv eccentrically or'v the longitudinal" center line-of said bushing;` Thel looper Sl i`ss'pa'ced from one end face'ofI the bushing Idby a-collar Il secured upon-thelooper-sha-ft I3`b'y the loop-Av er-shank fasteningscreWsII; said-collar I'lfun'cll tioning to confine theloopereshaft lf3v against endwse movement inv onev` direction, and!y alsb serving to conne the needle-roller bearing ad# jacent said-collari The' looper-shaft I extendsentirely through the bushing I6 and carries-a;` gear-Wheel Eiex?L terna-Hy of` and adjacenttliej end facev of thex bushing opposite'l the'looper 9`i` said gear-wheelz being preferably integralv with the looper-shaft I3. Adjacent the gear-Wheel I8-, the'looper-shaft`- I3 has a shoulder I9 confining the otheroi the needle-roller bearings'` lillof lthelooper-shaft.

In driving`engagementAL with! the looper-shaft gear-wheel I 8 iis 'afninterrnediat'e''v gear-wheel 2 il? integral Awith or-othewisel carriedl byI one' en'dof a-lhorizontal stub-shaftv 2-I` disposed;substa'ntiallyf parallel to thetlooper-sliaft' 35 bearings 22 disposedl in thefopposite endsf'of a'i longitudinal bore'lZS provided. in the bushing. IS

eccentrically of the longitudinal center'lineofi the bushing. The intermeshing gearewh'ee-ls I 85' `ing I5, i. e., said gear-Wheels arefboth/ disposedf within the eld of the projected end face of-the bushing. The stub-shaft. 2I- also. has a rollerbearing confining shoulder 2li at the gear endfof said smb-shaft. The other" cnn of the Saib-l shaft 2I extends beyond the opposite end of the bushing I6 and carries a collar 25 secured upon said stub-shaft 2I by a screw 25.

The looper-shaft I3, the looper S carried thereby, and the stub-shaft 2l, together with the intermeshing gears I8 and 26, and the roller-bearings for said shafts, may be assembled in the bushing i6 to form a separate assembly unit as illustrated in Fig. 2' of the drawing. As the gears I 3 and 20 do not extend radially beyond the circumferential bounds of the bushing I6, the bushing may be endwise inserted into a horizontal opening 2l of a casing-wall Z8 depending from the bed-plate I. The bushing I5 is adjustably secured by a screw 29 in the casing-wall 28 so that the gears side of said wall opposite the looper 9.

e The stub-shaft 2| is also` rotatably journaled: insY needle-roller-4I I 8, 20 are disposed at thev ing from the bed-plate I; said casing also including a front wall 3S and a rear wall 37. A bottom closure-plate 38, secured by screws 39 to said casing walls, provides a lubricant k reservoir 4D housing the gears I8, 20 and 30.

At its opposite end, the bed-shaft 33 is journaled in a ball-bearing 4I supported by a lug 42 depending from the bed-plate I. Adjacent the ball-bearing 4I, the bed-shaft 33 carries a pulleyl 43 engaged by a belt 44 which is driven to rotate the bed-shaft 33 once for each complete reciprocation of the needle 5.

The hub 3I of the bed-shaft spur-gear is circumferentially recessed to provide a seat for a lubricant-splasher 45 adapted to dip into a supply of lubricant contained in the reservoir 40. The bore I2 of the looper-shaft I3 is provided with a wick 4B protruding slightly from the end of the looper-shaft which extends into the reservoir 40. Lubricant splashed upon the wick 46 is fed thereby lengthwise of the looper-shaft I3 to diametral shaft-apertures 41 leading to the needle-roller bearings I4,

The stub-shaft 2I is also provided with a longitudinal bore 48 provided with a wick 49 extending into the reservoir 40 from the gear end of said stub-shaft; the wick 49 feeding lubricant supplied thereto by the splasher 45 to diametral stub-shaft apertures 50 leading to the needleroller bearings 22.

Having thus set forth the nature of the invention what we claim herein is:

1. A looper-mechanism assembly unit for chain-stitch sewing machines, comprising, a bushing, a looper-shaft rotatably journaled in said bushing, a rotary looper carried by said shaft, a gear-wheel carried by said shaft, and a second gear-wheel rotatably supported by said bushing in driving engagement with the looper-shaft gear-wheel, said gear-wheels being both disposed l within the produced circumferential bounds of the bushing.

2. A looper-mechanism` assembly unit for chain-stitch sewing machines, comprising, a bushing lengthwise provided with a bearing-bore, a looper-shaft rotatably journaled in said bearing-bore of the bushing, a looper carried by one end of said shaft, a gear-wheel carried by the other end of said shaft, and a second gear-wheel rotatably supported by said bushing in driving engagement with the looper-shaft gear-wheel, said gear-wheels being both disposed externally of one endof said bushing within the produced circumferential bounds of the bushing.

3. A looper-mechanism assembly unit for lchain-stitch sewing machines, comprising, a

bushing, a looper-shaft extending lengthwise of and rotatably journaled in said bushing, a rotary wing-type looper carried by said shaft adjacent one end of said bushing, a gear-wheel carried by said shaft, and a second gear-wheel rotatably supported by said bushing in driving engagement A with the looper-shaft gear-wheel, said gear- Wheels being both disposed adjacent the end of said bushing opposite the looper end thereof and Vwithin the produced circumferential bounds of the bushing.

' 4. A looper-mechanism assembly unit for chain-stitch sewing machines, comprising, a bushing lengthwise provided with substantially parallel bearing-bores, a looper-shaft disposed in one of said bearing-bores and having a longitudinal bore, a second shaft disposed in the other of said bearing-bores, and having a longitudinal bore, antifriction bearings for said shafts in the bearing-bores of said bushing, a looper carried by one end of the looper-shaft externally of one end of said bushing, a gear-wheel carried by the other end of said looper-shaft externally of the other end of said bushing! a gear-wheel carried by said second shaft and in driving engagement with the looper-shaft gear-wheel, and wicks disposed in the respective bores of said shafts, said shafts having radial apertures leading from the bores of the shafts to said antifriction bearings. 5. A sewing machine having a frame including a bed-plate, a wall depending from said bed-plate having a horizontal opening, a bushing secured in said opening of the bed-plate wall, said bushing being lengthwise provided with albearingbore, a looper-shaft rotatably journaled in said bearing-bore of the bushing, a looper carried by one end of said shaft at one side of said wall, a gear-wheel carried by said looper-shaft at the opposite side of said wall, an intermediate gearwheel rotatably supported by said bushing in driving engagement with the looper-shaft gearwheel, said gear-wheels being both disposed within the produced circumferential bounds of the bushing, a bed-shaft rotatably journaled in said 

